88'camaro305TBI

iTrader: (2)

My plans are to convert my 406 to a roller valvetrain, add a bigger cam (Comp XE 274, maybe 284) and possibly reuse the existing heads. Can someone tell me what kind of heads these are and if its worth any time porting them? My goal is to achieve at least 450hp out of this engine. It has about 20,000 miles on it after a rebuild - all i know is that it has aftermarket rods with 4bolt mains with ARP bolts, crankshaft has been turned .10 .10 (dont know what that means) ,block has been decked to 0 , Keith Black pistons,and compression is just under 10.0

Here are the casting numbers i have found on the heads:
Head1:
"8851598" "J28 9" "GM15" "CONV4"
Head2:
"8851598" "K6 8" "GM13" "CONV4" "441 (underneath intake valve)"

88'camaro305TBI

iTrader: (2)

another pic

88'camaro305TBI

iTrader: (2)

intake side

88'camaro305TBI

iTrader: (2)

combustion side

Sitting Bull

450 hp is not really easy to achieve and still have a nice daily driver. I'd aim for maybe 375 to 400 hp. Somewhat less expensive to reach, too. And your drivetrain might last a little longer. 400 to 450 hp will eat your stock tranny and rear end in short order.

Don't know about the heads but most of the fellows don't like the stock 400 heads at all.

88'camaro305TBI

iTrader: (2)

It is not a daily driver, just for fun.
It currently makes close to 370, 380 hp, but i want more out of this motor - its got a RV cam - don't know the specs, Rhode lifters, basically built for torque and meant to go inside a pickup truck. It falls flat on its face after 4,800 rpm. I would like a power band that will take me to 5,500 rpm with good power.
If those are the stock 400 heads than i will get rid of them. Thinking about some Canfields instead.

BTW - my rear end is a 9bolt with fresh gears (3.73's or 3.71's - can't remember)
Tranny going in is Spohn's Tremec 6spd

Stekman

That number looks like the 1970ish i think it was 76cc chamber 400ci heads.

Sitting Bull

Revving the 400 past 5000 rpm is not recommended unless you have beefed up the internals considerably. Even the factory 4 bolt main 400s aren't good revvers. But I've heard good things about the 2 bolt mains that are fitted with aftermarket 4 bolt setups.

RB83L69

There's no number quite like that; however, there is one that's real close, the same in fact except that the first digit is a 3. Form Mortec: So I'd suspect that's what they are.

Very poor head. Early smoggers, from back when they were creating "EGR" by using restrictive exhaust ports, thereby forcing some of the exhaust gas to remain in the engine. So, there's no way it's making 375 HP right now. I'd be real surprised if it cracked 325 HP. It takes RPM to make HP (after all, HP is torque times RPM divided by 5252.11), and if its power band is at a lower RPM than some stock 305s as you say it is, then .... well do the math.

Sounds like you have the foundation of a good short block, but somebody really missed big-time on the heads.

450 HP out of a 400 is not particularly difficult at all, and doesn't require making it near as un-streetable as the same HP out of a 350. Plus, it will have more torque at all RPMs, which is even better as a street motor.

Have those melted down; and get something good. Dart Iron Eagles would be a decent but not too expensive way to go. A set of 200 those with the 1.55" spring upgrade, a Comp XE274, 1.6 roller rockers, a Performer RPM, and 1/75" headers should put you right there, with a combo you can dirve to work every day and get 18 mpg on the highway with. Lose the Rhoads lifters. Pick the chamber size such that, along with whatever pistons are in the motor, you end up with about 10:1 CR. Forget both TBI and TPI, neither one will give you anywhere nesar the results of a simple carb. A 750 Holley or Demon with manual secondaries is the way to go.

Damon

They're just junk smogger castings with 76cc bathtub chambers. Not for performance use. ANYTHING aftermarket will work a lot better than them. Just remember if you go with aftermarket heads to have them drilled for the 6 "steam holes" that are unique to heads used on a 400 block.

The stock bottom end I wouldn't trust beyond 5000 RPMs. Rod bolts are usually the first thing that lets go. However, with upgraded rod bolts (ARP Waveloc- accept no substitute) and some aftermarket flat top pistons you have an excellent foudation for making some serious power up to ~6000-6200 RPMs. Even using the stock "shortie" connecting rods. I ran a combo exactly like that to high 11s on nitrous. HUNDREDS of runs, tens of thousands of street miles.

400HP is easy from a 400. Doesn't require more than some decent aftermarket heads and a mild cam with about 215* duration. Very streetable. 450HP gets tougher to do with good drivability, but it's a whole lot easier than it was in the old days. There are so many good aftermarket heads available these days. Heads are where the power is. Always have been, always will be. And on a big cube motor, more flow drops stright to the bottom line, horsepower-wise.

88'camaro305TBI

iTrader: (2)

Thanks for all the help guys.
I already have a holley 750 double pumper w/ shaved choke tower and a single plane intake manifold.
What do you guys think of the Canfield 195's - I could get those from Competition Products for about the same price as the Dart Iron Eagles and the Canfields are aluminum and flow better.

But first i think i'm going to take my shortblock and have it looked over by an engine builder to see how stout the crankshaft is. The guy that sold the engine to me said it has ARP bolts on the mains and aftermarket rods along with Keith Black pistons. But its the same guy that said it should be making 380 hp, which it probably is not, so i better get it checked out. Would you guys be able to tell by looking as some pictures?

BTW - the car ran low 5's 0-60 and low 14's in the 1/4 before i took it apart (and that was with a t-5 which is now on its last leg)

RB83L69

The Canfields are a good head too; make sure you bump the CR up a bit, like aim for around 10.5-10.8 or so; and make sure you're not so price-driven that you get weenie valve springs. Get better valve springs than you think you're going to need because you'll need them whether you know it yet or not.

Yes, pics would help. In particular pics of the pistons, and the crank. We can probably tell what they are and whether they're appropriate to your goal.

Fast305

Vortecs might work on this combo. He can have performance and mileage. I have played around on DD2000 and put in a very mild 400 with stock vortec heads and a similar cam. The output came up to be about 400 hp @ 5,000 and 475 tq @ 3,000.

A 400 will never rev very high if it has the stock 5.565" rods in it.

88'camaro305TBI

iTrader: (2)

Here are the pics of the bottom end

88'camaro305TBI

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another

88'camaro305TBI

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last one

RB83L69

Hmmm....

Cast stock crank; stock rods; look like stock rod bolts to me. Bummer.

I wouldn't go jamming a bunch of cams and heads that will give high flow and high RPMs on top of that, without a little work.

What pistons are they? Stock too?

Looks like maybe all you've really got there is a block core.

88'camaro305TBI

iTrader: (2)

Thanks RB for all the answers, looks like i got royally screwed. At this point, it might be more cost effective to get a whole new built-up short block rather then dumping money into this engine (if you take into account a professional machinist to install a new crank and rods and balancing and all that). Here is one last pic of the piston.
"How much would i have to put into this block to get what i want out of it and what kind of parts would i need? There is so many different cranks and rods out there it makes my head spin. Would i be able to do the work myself or would i need a pro?"
thanks again

RB83L69

That's a common TRW / Speed Pro one.... forged. Some people think they're heavy for performance usage, but they're a whole lot better than stock. If the block doesn't need bored, then those could probably be re-used.

Look at Lunati and Eagle, for not-too-$$$ cranks and rods that would work well for what the rest of the motor will want. The Eagle SIR stuff would be fine for example.

What kind of shape is the bore in? Do you know if it was bored & honed with a torque plate? If so, and there's less than a couple of thousandths of wear on it, you can likely get away with getting a new crank and hanging those pistons on a better set of rods and putting it back together. If you could re-use them, it would save you about $30-35 apiece, more or less.

There's nothing really "wrong" with what you've got, it's just not enough short block for what you're planning to put on top of it. I guess whether you got "screwed" would depend on what you paid. If you didn't pay more than about $500, you did OK; that's about what that block and a set of those pistons would typically go for on the open market. Plus, you may have got some re-usable machine work on top of that. So, I'd put the "screwed" threshold at about $600-700 or so.

88'camaro305TBI

iTrader: (2)

The bores have clearly visible x-marks on them - which i'm guessing is a part of the honing process? I don't know if it was done using a torque plate. The engine has roughly about 20,000 miles on it since the rebuilt. I have used nothing but Mobil 1 Synthetic since i got the engine. As far as checking the wear on it, i don't have any specialized tools or micrometers to do that.

RB83L69

Well you've got what looks like a machine shop work order # on there.... 19337.... you might want to ask the PO where he had his work done, then call them up and see what was on that WO.

88'camaro305TBI

iTrader: (2)

I'm taking the block to the machine shop on Tues. and have them deal with the bottom end. I would feel too uncomfortable doing the work myself since i know next to nothing about it. I'll keep you guys posted on what happens to it, thanks.

88'camaro305TBI

iTrader: (2)

The engine is half-way there. We've decided on
- Eagle 4340 steel crankshaft
- Eagle 4340 3-D rods
- Clevite 77 H-series race bearings
- Wiseco Pro-Tru pistons and rings
- bored & honed with a torque plate, decked
- 10:1 compression w/ 76cc heads
- 11:4 compression w/ 64cc heads

The bottom end is already assembled, and now i need help with the top end. I want to go with AFR 210's, (their flow numbers are amazing). I need help choosing the right cam and valve train components. It is going to be a hydraulic roller setup. The car is not a daily driver, but i don't want to go overkill on the street with a solid roller setup (unless someone can talk me into it). What is the biggest hydraulic roller cam i can go with? What valvetrain components should i get with it?
I want to go with Comp Cams Pro Magnum roller rockers but what ratio should i go with?
"p.s. I'm leaning towards the 10:1 compression heads because i would like to go with a blower later down the road. "

92rs85berlintta

iTrader: (1)

isnt that too high for a blower???

88'camaro305TBI

iTrader: (2)

yeah, 10:1 is a bit high for a blower, but i can always port the heads to lower the CR

masseyiroc

i had almost the same motor as this guys last season 4 bolt main,short rods with arp blots ,exact same pistons,274 xe cam but with protopline heads.that motor had 1 season of 100 1/4 passes on it and about 5000 street miles.the more i reved it the faster 1/4 it got ,shift point 6400rpm.best pass 12.56 @109.everyone told me the same thing that iot wouldnt rev.lol

92rs85berlintta

iTrader: (1)

i didnt think porting lowers compression? or do you mean cc them to take off some metal. dish piston might be an option as well.

MrDude_1

if its a toy, go solid roller.

masseyiroc

mine has a xtreme energy solid roller now the boost in power is nice.

88'camaro305TBI

iTrader: (2)

what kind of RPM range are you guys getting using a solid roller?

masseyiroc

mine is rated from 2500-6500 .its in the sig.

jwscab

No, I don't think you got screwed if you didn't pay more than about 500-600 bucks. As for your build-up, if you're looking for 400-450 HP, theres no reason to get all that forged internal stuff, unless its cheap. A cast 400 crank will live perfectly happy if the journals are straight. The rods, eh, I would put better rods in it, but even then, you don't need anything more than a good forged rod, no H beam, etc. Put in fresh ARP bolts in the bottom end(or even studs) and you'd have a decent bottom end. Then spend the money on a good set of heads. As for the 'race' bearings, just use good clevite or michigan 77 bearings, for stock journals, no narrowed bearings or anything like that, they tend to wear alot faster than you think.

a good idea is lightweight pistons though, and shoot for about 10-10.5 to 1. if you're not driving everyday, and using it for track use, bump that up to 11.5 to 1. Bump that up a bit if you're using aluminum heads.

think about your build realistically, 450 horse out of a 400 is do-able, but you're not pushing the envelope, too many guys I see spend all this $$$ on these killer bottom ends, and never capitalize on them. Especially if you are not lauching hard with a stick, on slicks. The whole secret to a bottom end living in a chevy is to balance the thing.

88'camaro305TBI

iTrader: (2)

thanks, jwscab, but the bottom end is already done with the components i listed above. I'm now shooting for a little over 500hp with AFR 210 heads. I did some more reasearch on solid roller cams and i want to go with a solid, i just don't know what size to go with yet. The reason i didn't cheap out on the bottom end is because i want to run a blower later on in the future, or nitrous. So what size solid roller cam would you guys recommend? thanks.

ME Leigh

A XR280R should be perfect. You don't need a super huge cam with AFR heads, the heads make the power. You may even want to go with a XR274R to make it a little funner to drive.